Apparatus for endoscopic procedures

ABSTRACT

A surgical device includes a jaw assembly, an articulating assembly and a drive shaft. The jaw assembly includes first and second jaws. The articulating assembly is removably coupled to a proximal end of the jaw assembly and includes a distal joint member, a proximal joint member, and a pivot pin. The pivot pin is fixedly coupled to the distal joint member and is rotatably coupled to the proximal joint member. The jaw assembly and the distal joint member together define a first longitudinal axis. The proximal joint member defines a second longitudinal axis. The drive shaft includes a gear element that is meshingly engaged with a pivoting gear element that is fixedly coupled to the pivot pin. Longitudinal movement of the first drive shaft pivots the jaw assembly relative to the proximal joint member about a pivot axis defined by the pivot pin.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a Continuation of U.S. patent application Ser. No. 16/158,456, filed Oct. 12, 2018, which is a Continuation-in-Part of U.S. patent application Ser. No. 16/158,427, filed Oct. 12, 2018, which claims the benefit of U.S. Provisional Patent Application Ser. No. 62/578,673, filed Oct. 30, 2017, the entire contents of each of which are incorporated by reference herein.

TECHNICAL FIELD

The present disclosure relates to surgical apparatus, devices and/or systems for performing endoscopic surgical procedures and methods of use thereof. More specifically, the present disclosure relates to manual, electromechanical, robotic and/or hand-held surgical apparatus, devices and/or systems configured for use with removable disposable loading units and/or single use loading units for clamping, cutting and/or stapling tissue.

BACKGROUND

A number of surgical device manufacturers have developed product lines with proprietary drive systems for operating and/or manipulating electromechanical surgical devices. In many instances the electromechanical surgical devices include a handle assembly, which is reusable, and disposable loading units and/or single use loading units or the like that are selectively connected to the handle assembly prior to use and then disconnected from the handle assembly following use in order to be disposed of or in some instances sterilized for re-use.

Various electromechanical linkages are utilized to transmit power from the reusable handle assemblies, which include one or more motors, to the disposable loading unit to effect rotation, pivoting, clamping, fastener ejection, etc. Due to the complex structure and operation of the power transmission mechanisms inadvertent actuation of these mechanisms may result in unintended operation of the disposable loading unit, which may result in damage to the surgical device and/or injury to the patient. Robotic systems for performing minimally invasive surgery are also known. For example, International Application Publication WO 2000/051486 discloses a system having remotely-controlled surgical instruments.

Many of these electromechanical surgical devices are relatively expensive to manufacture, purchase and/or operate. There is a constant desire by manufacturers and end users to develop electromechanical surgical devices that are relatively inexpensive to manufacture, purchase and/or operate that still provide a large degree of operability with prerequisite safety features. Accordingly, a need exists for electromechanical surgical apparatus, devices and/or systems that include effective electromechanical transmission system for actuating the disposable units as well as safety lockout assemblies.

SUMMARY

In a first aspect of the present disclosure, a surgical stapling instrument comprises a reload including a staple cartridge assembly and an anvil assembly moveable with respect to one another. An adapter assembly has an elongate shaft and an articulating distal end, a mounting member being disposed at the distal end and being pivotally attached to the elongate shaft, the mounting member having a connection feature for attaching the reload to the adapter assembly. A drive mechanism is in the adapter, the drive mechanism including a bar extending through the mounting member and having a beam at a distal end of the bar, the bar being flexible and supported by a pair of bar guides, one of the bar guides alongside a first side of the bar, and the other of the bar guides being alongside a second side of the bar, the bar being further supported by a pair of blowout plates, one of the blowout plates being alongside the first side of the bar, and the other of the blowout plates being alongside the second side of the bar, the pair of blowout plates being distal to the pair of bar guides, the bar being further supported by a support block having an opening, the bar and the pair of blowout plates being disposed in the opening of the support block, the bar, the pair of bar guides, the pair of blowout plates, and the support block being pivotable from a central position in the adapter assembly to an off-center position in the adapter assembly.

The support block can be curved. The mounting member can have a curved slot. The support block can be disposed in the curved slot so that the support block is movable in the curved slot.

An articulation link extends inside the elongate shaft, and a second link pivotally connected to the articulation link and to the mounting member. The second link can be curved.

The bar can have a plurality of layers stacked together. The beam can have an upper flange and a lower flange. The bar can be attached to a threaded drive member. The threaded drive member may be disposed inside an inner tube having an interior thread. The connection feature can define a keyway. The reload may define a tab that is received in the keyway.

In another aspect, a surgical stapling system comprises: a hand-held instrument handle having a battery, a motor and computer and memory components; a removable and replaceable adapter assembly; a first linear surgical stapling reload having a first end effector, the first linear surgical stapling reload being removably and replaceably attachable to the adapter assembly; and a second linear surgical stapling reload having a second end effector and being removably and replaceably attachable to the adapter assembly, the second linear surgical stapling reload having a feature and the first linear stapling reload not having the feature, each of the first linear surgical stapling reload and the second linear surgical stapling reload having a staple cartridge assembly and an anvil assembly.

The adapter assembly corresponds to the first linear surgical stapling reload and the second linear surgical stapling reload. The feature can be a dissecting tip on a distal end of the anvil assembly of the second linear surgical stapling reload.

The feature can be a stapling buttress on each of the anvil assembly and the staple cartridge assembly of the second linear surgical stapling reload.

The handle can be sterilizable and re-used for a prescribed number of procedures.

In accordance with yet another aspect of the present disclosure, a surgical stapling system including a cartridge assembly is provided. The cartridge assembly includes a cartridge and a sled assembly configured to drive fasteners through the cartridge. The cartridge has a tissue-contacting surface. The sled assembly includes a knife pivotally coupled to the sled assembly. The knife has a blade and is positioned to pivot distally from a first position where the blade is disposed below the tissue-contacting surface to a second position where the blade is disposed above the tissue-contacting surface.

In some embodiments, the sled assembly may include knife mount that has a blocking surface. The blocking surface may extend over the knife and may be positioned to support the knife in the second position. The knife may include a knife arm that is coupled to the knife mount by a pivot pin to enable the knife to pivot relative to the knife mount. The knife may be coupled to a spring that is engaged with the knife mount and positioned to urge a distal foot of the knife arm distally so that the blade, which is supported on a proximal portion of the knife arm, is urged toward the first position. The knife mount may include a stabilizing finger that extends from the knife mount to support the knife when the knife is in the second position.

Further details and aspects of exemplary embodiments of the present disclosure are described in more detail below with reference to the appended figures.

BRIEF DESCRIPTION OF THE DRAWINGS

Embodiments of the present disclosure are described herein with reference to the accompanying drawings, wherein:

FIG. 1 is a perspective, disassembled view of an electromechanical surgical system including a surgical instrument, an adapter assembly, and an end effector, according to the present disclosure;

FIG. 2 is a perspective view of the surgical instrument of FIG. 1 , according to the present disclosure;

FIG. 3 is perspective, disassembled view of the surgical instrument of FIG. 1 , according to the present disclosure;

FIG. 4 is a perspective view of a battery of the surgical instrument of FIG. 1 , according to the present disclosure;

FIG. 5 is a top, partially-disassembled view of the surgical instrument of FIG. 1 , according to the present disclosure;

FIG. 6 is a front, perspective view of the surgical instrument of FIG. 1 with the elongated member separated therefrom, according to the present disclosure;

FIG. 7 is a cross-sectional side view of the surgical instrument of FIG. 1 , as taken through 7-7 of FIG. 1 , according to the present disclosure;

FIG. 8 is a top, cross-sectional view of the surgical instrument of FIG. 1 , as taken through 8-8 of FIG. 1 , according to the present disclosure;

FIG. 9 is a perspective, disassembled view of a control assembly of the surgical instrument of FIG. 1 , according to the present disclosure;

FIG. 10 is a perspective view of the adapter assembly of FIG. 1 having an articulating neck assembly, according to the present disclosure;

FIG. 11 is a perspective, partial cross-sectional view of the adapter assembly of FIG. 1 , according to the present disclosure;

FIG. 12 is a perspective view of an end effector connected to a distal end of the adapter assembly of FIG. 1 , oriented in a linear, non-articulated orientation, according to the present disclosure;

FIG. 13 is a disassembled view of the end effector of FIG. 12 , according to the present disclosure;

FIG. 14 is a perspective, cross-sectional view of the end effector of FIG. 12 , according to the present disclosure;

FIG. 15 is an enlarged, cross-sectional side view of the end effector of FIG. 12 , according to the present disclosure;

FIG. 16 is an enlarged, cross-sectional side view of the end effector of FIG. 12 disconnected from the articulating neck assembly, according to the present disclosure;

FIG. 17A is a disassembled view of the articulating neck assembly according to the present disclosure;

FIG. 17B is a perspective view of part of the articulating neck assembly according to the present disclosure;

FIG. 18 is a top perspective, partially-disassembled view of the articulating neck assembly according to the present disclosure;

FIG. 19 is a bottom perspective, partially-disassembled view of the articulating neck assembly according to the present disclosure;

FIG. 20 is a side perspective, partially-disassembled view of the articulating neck assembly according to the present disclosure;

FIG. 21 is a top perspective, partially-disassembled view of the articulating neck assembly according to the present disclosure;

FIG. 22 is a top perspective view of the articulating neck assembly according to the present disclosure;

FIG. 23 is a side view of the articulating neck assembly in an articulated orientation, according to the present disclosure;

FIG. 24 is an enlarged, cross-sectional side view of the end effector of FIG. 12 connected to the articulating neck assembly, according to the present disclosure;

FIG. 25 is a cross-sectional side view of the end effector of FIG. 12 connected to the articulating neck assembly oriented in a linear, non-articulated orientation, according to the present disclosure;

FIG. 26 is a cross-sectional side view of the end effector of FIG. 12 connected to the articulating neck assembly oriented in a first articulated orientation, according to the present disclosure;

FIG. 27 is a cross-sectional side view of the end effector of FIG. 12 connected to the articulating neck assembly oriented in a second articulated orientation, according to the present disclosure;

FIG. 28 is a perspective view of another embodiment of an articulating neck assembly with an end effector connected to a distal end of the adapter assembly of FIG. 1 , oriented in a linear, non-articulated orientation, according to the present disclosure;

FIG. 29 is a perspective, disassembled view of the articulating neck assembly of FIG. 28 according to the present disclosure;

FIG. 30 is a top perspective, partially-disassembled view of the articulating neck assembly of FIG. 28 according to the present disclosure;

FIG. 31 is a cross-sectional, side view of the end effector connected to the articulating neck assembly of FIG. 28 oriented in a linear, non-articulated orientation, according to the present disclosure;

FIG. 32 is a cross-sectional, side view of the end effector connected to the articulating neck assembly of FIG. 28 oriented in a first articulated orientation, according to the present disclosure;

FIG. 33 is a cross-sectional, side view of the end effector connected to the articulating neck assembly of FIG. 28 oriented in a second articulated orientation, according to the present disclosure;

FIG. 34 is a perspective view of a surgical system including a surgical stapling instrument having an adapter assembly and an end effector reload according to another aspect of the present disclosure;

FIG. 34A is an elevation view of the end effector reload and the distal end of the adapter assembly;

FIG. 35 is a perspective view of an adapter assembly and an end effector reload for the surgical stapling instrument;

FIG. 36 is a cross-sectional view of the adapter assembly for the surgical stapling instrument of FIGS. 34-35 ;

FIG. 37 is a perspective view of the articulating portion of the adapter assembly;

FIG. 38 is a cross-sectional view of the articulating portion of the adapter assembly;

FIG. 39 is a perspective view of the articulating portion of the adapter assembly;

FIG. 39A is a cross-sectional view of the proximal end of the adapter assembly;

FIG. 39B is a perspective view of the lead screw of the adapter assembly;

FIG. 40 is a perspective view of an I-beam for the surgical stapling instrument;

FIG. 40A is a perspective view of the I-beam and sled for the surgical stapling instrument;

FIG. 40B is a perspective view of the I-beam and sled for the surgical stapling instrument;

FIG. 41 is a perspective view of the articulation mechanism in the proximal end of the adapter assembly;

FIG. 42 is a cross-sectional view of the articulation mechanism in the proximal end of the adapter assembly;

FIG. 43 is a plan view of the articulation mechanism in the distal end of the adapter assembly;

FIG. 44 is a plan view of the articulation mechanism in the distal end of the adapter assembly;

FIG. 45 is a perspective view of the articulation mechanism in the distal end of the adapter assembly;

FIG. 45A is a perspective view of a gear assembly in the adapter assembly;

FIG. 46 is a perspective view of the end effector reload and distal end of the adapter assembly;

FIG. 47 is a perspective view of the proximal end of the end effector reload;

FIG. 48 is a plan view of the end effector reload and distal end of the adapter assembly;

FIG. 48A is a cross-sectional view of the end effector reload and distal end of the adapter assembly;

FIG. 49 is a perspective view of the adapter assembly and end effector reload showing the reload unattached to the adapter assembly;

FIG. 50 is an exploded view of the staple cartridge assembly and anvil assembly;

FIG. 51 is a plan view of a different example of an articulation mechanism in the distal end of an adapter assembly;

FIG. 52 is a perspective view of another embodiment of an end effector of the electromechanical surgical system of FIG. 1 , the end effector illustrated in an unclamped position;

FIG. 52A is a perspective view illustrating the end effector of FIG. 52 secured to the electromechanical surgical system of FIG. 1 ;

FIG. 53 is a perspective view of the end effector of FIG. 52 with a cartridge assembly of the end effector shown separated from a tool assembly of the end effector;

FIG. 54 is a perspective view, with parts separated, of the cartridge assembly of FIG. 53 ;

FIG. 55 is an enlarged perspective view of a sled assembly of the cartridge assembly of FIG. 54 , the sled assembly including a blade shown in a first position;

FIG. 56 is a perspective view of the sled assembly of FIG. 55 with the blade thereof shown in a second position;

FIG. 57 is a side, cross-sectional view of the sled assembly of FIGS. 55 and 56 as taken along section line 57-57 seen in FIG. 55 ;

FIG. 58 is a side, cross-sectional view of the sled assembly of FIGS. 55 and 56 as taken along section line 58-58 seen in FIG. 56 ;

FIG. 59 is a perspective view, with parts separated, of the sled assembly of FIGS. 55 and 56 ;

FIG. 60 is a side, cross-sectional view of the end effector of FIG. 52 as taken along section line 60-60 shown in FIG. 52A, the end effector shown in a clamped position;

FIGS. 61-62 are enlarged progressive views of the indicated area of detail shown in FIG. 60 ; and

FIG. 63 is a perspective view illustrating the blade of the sled assembly of FIGS. 55 and 56 in the second position and engaged with an I-beam of the end effector of FIG. 52 .

DETAILED DESCRIPTION

Embodiments of the presently disclosed electromechanical surgical system, apparatus and/or device are described in detail with reference to the drawings, in which like reference numerals designate identical or corresponding elements in each of the several views. As used herein the term “distal” refers to that portion of the electromechanical surgical system, apparatus and/or device, or component thereof, that are farther from the user, while the term “proximal” refers to that portion of the electromechanical surgical system, apparatus and/or device, or component thereof, that are closer to the user. The terms “left” and “right” refer to that portion of the electromechanical surgical system, apparatus and/or device, or component thereof, that are on the left and right sides, respectively, from the perspective of the user facing the distal end of the electromechanical surgical system, apparatus and/or device from the proximal end while the surgical system, apparatus and/or device is oriented in non-rotational configuration.

Reference may be made to International Application Publication No. WO 2009/039506, U.S. Pat. No. 9,775,610, and U.S. Patent Application Publication US 2011/0121049, the entire contents of each of which are incorporated by reference herein, for a detailed description of the construction and operation of exemplary electromechanical, hand-held, powered surgical instrument 100.

Referring initially to FIGS. 1-8 , an electromechanical, hand-held, powered surgical system, in accordance with an embodiment of the present disclosure is shown and generally designated 10. Electromechanical surgical system 10 includes a surgical apparatus or device in the form of an electromechanical, hand-held, powered surgical instrument 100 that is configured for selective attachment thereto of a plurality of different end effectors 300, via an adapter assembly (e.g., elongated body) 200. The end effector 300 and the adapter assembly 200 are configured for actuation and manipulation by the electromechanical, hand-held, powered surgical instrument 100. In particular, the surgical instrument 100, the adapter assembly 200, and the end effector 300 are separable from each other such that the surgical instrument 100 is configured for selective connection with adapter assembly 200, and, in turn, adapter assembly 200 is configured for selective connection with any one of a plurality of different end effectors 300.

The end effector and/or adapter can be configured as an integral unit in any of the embodiments disclosed herein. The end effector and/or adapter can be configured for use with a powered handle, console, and/or surgical robot, in any of the embodiments disclosed herein.

As illustrated in FIGS. 1-3 , the hand-held surgical instrument 100 includes a handle housing 102 having a lower housing portion 104, an intermediate housing portion 106 extending from and/or supported on lower housing portion 104, and an upper housing portion 108 extending from and/or supported on intermediate housing portion 106. Intermediate housing portion 106 and upper housing portion 108 are separated into a distal half-section 110 a that is integrally formed with and extending from the lower portion 104, and a proximal half-section 110 b connectable to distal half-section 110 a by a plurality of fasteners. When joined, distal and proximal half-sections 110 a, 110 b define a handle housing 102 having a cavity 102 a therein in which a circuit board 150 and a drive mechanism 160 are situated.

With reference to FIGS. 2 and 3 , distal and proximal half-sections 110 a, 110 b are divided along a vertical plane that traverses a longitudinal axis “A-A” of upper housing portion 108 (FIG. 2 ). Handle housing 102 includes a gasket 112 extending completely around a rim of distal half-section and/or proximal half-section 110 a, 110 b and being interposed between distal half-section 110 a and proximal half-section 110 b. Gasket 112 seals the perimeter of distal half-section 110 a and proximal half-section 110 b. Gasket 112 functions to establish an air-tight seal between distal half-section 110 a and proximal half-section 110 b such that circuit board 150 and drive mechanism 160 are protected from sterilization and/or cleaning procedures.

In this manner, the cavity 102 a of handle housing 102 is sealed along the perimeter of distal half-section 110 a and proximal half-section 110 b yet is configured to enable easier, more efficient assembly of circuit board 150 and a drive mechanism 160 in handle housing 102.

Intermediate housing portion 106 of handle housing 102 provides a housing in which circuit board 150 is situated. Circuit board 150 is configured to control the various operations of surgical instrument 100, as will be set forth in additional detail below.

Lower housing portion 104 of surgical instrument 100 defines an aperture (not shown) formed in an upper surface thereof and which is located beneath or within intermediate housing portion 106. As shown in FIGS. 3 and 4 , the aperture of lower housing portion 104 provides a passage through which wires 152 pass to electrically interconnect electrical components situated in lower housing portion 104, e.g., a battery 156 and a circuit board 154, with electrical components situated in intermediate housing portion 106 and/or upper housing portion 108, e.g., circuit board 150, drive mechanism 160, etc.

Handle housing 102 includes a gasket 107 disposed within the aperture of lower housing portion 104 thereby plugging or sealing the aperture of lower housing portion 104 while allowing wires 152 to pass therethrough (see FIG. 3 ). Gasket 107 functions to establish an air-tight seal between lower housing portion 106 and intermediate housing portion 108 such that circuit board 150 and drive mechanism 160 are protected from sterilization and/or cleaning procedures.

With continued reference to FIGS. 3 and 4 , lower housing portion 104 of handle housing 102 provides a housing in which the battery 156 is removably disposed therein. The battery 156 may be a rechargeable battery (e.g., lead-based, nickel-based, lithium-ion based, etc.). It is also envisioned that the battery 156 may be a single-use, non-rechargeable battery. Battery 156 is configured to supply power to any of the electrical components of surgical instrument 100. Lower housing portion 104 defines a cavity (not shown) into which battery 156 is inserted. Lower housing portion 104 includes a door 105 pivotally connected thereto for closing cavity of lower housing portion 104 and retaining battery 156 therein.

With continued reference to FIGS. 3 and 5 , distal half-section 110 a of upper housing portion 108 defines a nose or connecting portion 108 a. A nose cone 114 is supported on nose portion 108 a of upper housing portion 108. Nose cone 114 is fabricated from a transparent, light-transmissive material. An illumination member 116 is disposed within nose cone 114 such that illumination member 116 is visible therethrough. The nose cone 114 may be tinted, such that the illumination member 116 is visible when it is activated.

With reference to FIG. 5 , the illumination member 116 may include a plurality of any suitable light emitting devices, such as light emitting diodes (LEDs), disposed on printed circuit board (LED PCB) 116 a which is disposed in a vertical plane transverse to the longitudinal axis “A-A.” The illumination member 116 is configured to illuminate in multiple colors with a specific color pattern being associated with a unique discrete event. In embodiments, the LEDs may be single-color or multi-color LEDs.

Upper housing portion 108 of handle housing 102 provides a housing in which drive mechanism 160 is situated. As illustrated in FIG. 5 , drive mechanism 160 is configured to drive shafts and/or gear components in order to perform the various operations of surgical instrument 100. In particular, drive mechanism 160 is configured to drive shafts and/or gear components in order to selectively move tool assembly 304 of end effector 300 relative to the adapter assembly, to rotate end effector 300 about the longitudinal axis “A-A” (FIG. 2 ) relative to handle housing 102, to move anvil assembly 306 relative to cartridge assembly 308 of end effector 300, and/or to fire a stapling and cutting cartridge within cartridge assembly 308 of end effector 300.

The drive mechanism 160 includes a selector gearbox assembly 162 that is located immediately proximal relative to adapter assembly 200. Proximal to the selector gearbox assembly 162 is a function selection module 163 having a first (e.g., selector) motor 164 that functions to selectively move gear elements within the selector gearbox assembly 162 into engagement with an input drive component 165 having a second (e.g., drive) motor 166.

As illustrated in FIGS. 1-4 , distal half-section 110 a of upper housing portion 108 defines a connecting portion 108 a configured to accept a corresponding shaft coupling assembly 214 of adapter assembly 200.

As illustrated in FIGS. 6-8 , connecting portion 108 a of surgical instrument 100 has a cylindrical recess 108 b that receives the adapter assembly 200 when adapter assembly 200 is mated to surgical instrument 100. Connecting portion 108 a houses three rotatable drive connectors 118, 120, 122.

With reference to FIG. 6 , when adapter assembly 200 is mated to surgical instrument 100, each of rotatable drive connectors 118, 120, 122 of surgical instrument 100 couples with a corresponding rotatable connector sleeve 218, 220, 222 of adapter assembly 200. In this regard, the interface between corresponding first drive connector 118 and first connector sleeve 218, the interface between corresponding second drive connector 120 and second connector sleeve 220, and the interface between corresponding third drive connector 122 and third connector sleeve 222 are keyed such that rotation of each of drive connectors 118, 120, 122 of surgical instrument 100 causes a corresponding rotation of the corresponding connector sleeve 218, 220, 222 of adapter assembly 200.

In the above-described embodiments, the hand-held surgical instrument 100 may include a first (e.g., selector) motor 164 that functions to selectively move the selector gearbox assembly 162 gears into engagement with an input drive component having a second (e.g., drive) motor. In embodiments, other motor arrangements may be used, such as a different motor may be used for driving each of the connector sleeves. In further embodiments, other driving mechanisms for actuating the connector sleeves may be used, including, but not limited to, pneumatic and/or hydraulic drivers, solenoids, biasing members, and combinations thereof.

The mating of drive connectors 118, 120, 122 of surgical instrument 100 with connector sleeves 218, 220, 222 of adapter assembly 200 allows rotational forces to be independently transmitted via each of the three respective connector interfaces. The drive connectors 118, 120, 122 of surgical instrument 100 are configured to be independently rotated by drive mechanism 160. In this regard, the function selection module 163 of drive mechanism 160 selects which drive connector or connectors 118, 120, 122 of surgical instrument 100 is to be driven by the input drive component 165 of drive mechanism 160. The selector gearbox assembly 162 and the function selection module 163 are disclosed in more detail in a commonly-owned U.S. patent application Ser. No. 13/280,898, the entire contents of which is hereby incorporated by reference herein.

Since each of drive connectors 118, 120, 122 of surgical instrument 100 has a keyed and/or substantially non-rotatable interface with respective connector sleeves 218, 220, 222 of adapter assembly 200, when adapter assembly 200 is coupled to surgical instrument 100, rotational force(s) are selectively transferred from drive mechanism 160 of surgical instrument 100 to adapter assembly 200.

The selective rotation of drive connector(s) 118, 120 and/or 122 of surgical instrument 100 allows surgical instrument 100 to selectively actuate different functions of end effector 300. As discussed in greater detail below, selective and independent rotation of first drive connector 118 of surgical instrument 100 corresponds to the selective and independent opening and closing of tool assembly 304 of end effector 300, and driving of a stapling/cutting component of tool assembly 304 of end effector 300. Also, the selective and independent rotation of second drive connector 120 of surgical instrument 100 corresponds to the selective and independent articulation of tool assembly 304 of end effector 300 about an articulation axis “B-B” defined by a pin 505 (FIG. 12 ) that is transverse to longitudinal axis “A-A” (FIG. 2 ). In particular, the end effector 300 defines a second longitudinal axis “C-C” and is movable from a first position in which the second longitudinal axis “C-C” (FIG. 12 ) is substantially aligned with the first longitudinal axis “A-A” to at least a second position in which the second longitudinal axis “C-C” is disposed at a non-zero angle with respect to the first longitudinal axis “A-A.” Additionally, the selective and independent rotation of third drive connector 122 of surgical instrument 100 corresponds to the selective and independent rotation of end effector 300 about longitudinal axis “A-A” relative to handle housing 102 of surgical instrument 100.

As illustrated in FIGS. 5 and 8 , drive mechanism 160 includes a selector gearbox assembly 162; a function selection module 163, located proximal to the selector gearbox assembly 162, that functions to selectively move gear elements within the selector gearbox assembly 162 into engagement with second motor 166. Thus, drive mechanism 160 selectively drives one of drive connectors 118, 120, 122 of surgical instrument 100 at a given time.

As illustrated in FIGS. 1-3 and FIG. 9 , handle housing 102 supports a control assembly 103 on a distal surface or side of intermediate housing portion 108. Control assembly 103, in cooperation with intermediate housing portion 108, supports a pair of finger-actuated control buttons 124, 126 and rocker devices 128, 130. In particular, control assembly 103 defines an upper aperture 124 a for slidably receiving a first control button 124, and a lower aperture 126 b for slidably receiving a second control button 126.

Each one of the control buttons 124, 126 and rocker devices 128, 130 includes a respective magnet (not shown) that is moved by the actuation of an operator. In addition, circuit board 150 includes, for each one of the control buttons 124, 126 and rocker devices 128, 130, respective Hall-effect switches 150 a-150 d that are actuated by the movement of the magnets in the control buttons 124, 126 and rocker devices 128, 130. In particular, located immediately proximal to the control button 124 is a first Hall-effect switch 150 a (FIGS. 3 and 7 ) that is actuated upon the movement of a magnet within the control button 124 upon the operator actuating control button 124. The actuation of first Hall-effect switch 150 a, corresponding to control button 124, causes circuit board 150 to provide appropriate signals to function selection module 163 and input drive component 165 of the drive mechanism 160 to close a tool assembly 304 of end effector 300 and/or to fire a stapling/cutting cartridge within tool assembly 304 of end effector 300.

Also, located immediately proximal to rocker device 128 is a second Hall-effect switch 150 b (FIGS. 3 and 7 ) that is actuated upon the movement of a magnet (not shown) within rocker device 128 upon the operator actuating rocker device 128. The actuation of second Hall-effect switch 150 b, corresponding to rocker device 128, causes circuit board 150 to provide appropriate signals to function selection module 163 and input drive component 165 of drive mechanism 160 to articulate tool assembly 304 relative to the adapter assembly 200. Advantageously, movement of rocker device 128 in a first direction causes tool assembly 304 to articulate relative to the adapter assembly 200 in a first direction, while movement of rocker device 128 in an opposite, e.g., second, direction causes tool assembly 304 to articulate relative to the adapter assembly 200 in an opposite, e.g., second, direction.

Furthermore, located immediately proximal to control button 126 is a third Hall-effect switch 150 c (FIGS. 3 and 7 ) that is actuated upon the movement of a magnet (not shown) within control button 126 upon the operator actuating control button 126. The actuation of third Hall-effect switch 150 c, corresponding to control button 126, causes circuit board 150 to provide appropriate signals to function selection module 163 and input drive component 165 of drive mechanism 160 to open tool assembly 304 of end effector 300.

In addition, located immediately proximal to rocker device 130 is a fourth Hall-effect switch 150 d (FIGS. 3 and 7 ) that is actuated upon the movement of a magnet (not shown) within rocker device 130 upon the operator actuating rocker device 130. The actuation of fourth Hall-effect switch 150 d, corresponding to rocker device 130, causes circuit board 150 to provide appropriate signals to function selection module 163 and input drive component 165 of drive mechanism 160 to rotate end effector 300 relative to handle housing 102 surgical instrument 100. Specifically, movement of rocker device 130 in a first direction causes end effector 300 to rotate relative to handle housing 102 in a first direction, while movement of rocker device 130 in an opposite, e.g., second, direction causes end effector 300 to rotate relative to handle housing 102 in an opposite, e.g., second, direction.

Turning now to FIGS. 1 and 10 , adapter assembly 200 will be shown in detail and described. Adapter assembly 200 is configured to communicate the rotational forces of first, second and third rotatable drive connectors 118, 120, and 122 of surgical instrument 100 to end effector 300. As mentioned above, adapter assembly 200 is configured for selective connection to surgical instrument 100.

As seen in FIGS. 1, 6, 10, and 11 adapter assembly 200 includes an elongate, substantially rigid, elongate body portion 210 having a proximal end 210 a and a distal end 210 b; a transmission housing 212 connected to proximal end 210 a of elongate body portion 210 and being configured for selective connection to surgical instrument 100. The adapter assembly 200 also includes an articulating assembly 230 disposed at the distal end 210 b for coupling to the end effector 300.

In embodiments, the transmission housing 212 may include one or more gear train systems therein for varying a speed/force of rotation (e.g., increase or decrease) of first, second and/or third rotatable drive connectors 118, 120, and/or 122 of surgical instrument 100 before transmission of such rotational speed/force to end effector 300.

Transmission housing 212 of adapter assembly 200 is configured and adapted to connect to connecting portion 108 a of upper housing portion 108 of surgical instrument 100. As seen in FIGS. 1 and 6 , transmission housing 212 of adapter assembly 200 includes a shaft coupling assembly 214 supported at the proximal end 210 a

Adapter assembly 200 may include a first gear train system and a second gear train system, each disposed within transmission housing 212 and elongate body portion 210. Each gear train system is configured and adapted to vary a speed/force of rotation (e.g., increase or decrease) of first and second rotatable drive connectors 118 and 120 of surgical instrument 100 before transmission of such rotational speed/force to end effector 300. An adapter assembly having multiple gear trains is disclosed in more detail in a commonly-owned U.S. Pat. No. 8,899,462, the entire contents of which is hereby incorporated by reference herein.

As seen in FIG. 11 , adapter assembly 200 may rotatably support first, second, and third drive shafts 218 a, 220 a, 222 a, which include a proximal end connected to transmission housing 212, namely, corresponding rotatable connector sleeve 218, 220, 222. Each of the drive shafts 218 a, 220 a, 222 a also include a distal end extending to and operatively connected to the articulating assembly 230, as will be discussed in greater detail below. The elongate body portion 210 of adapter assembly 200 includes at least three longitudinally extending channels through body portion 210. The channels are configured and dimensioned to rotatably receive and support the drive shafts 218 a, 220 a, 222 a, which may be connected to respective gear systems (not shown). Each of the drive shafts 218 a, 220 a, 222 a are elongate and sufficiently rigid to transmit rotational forces from transmission housing 212 to articulating assembly 230, which are used to drive the end effector 300 as described in further detail below.

FIGS. 12-16 illustrate components and operation of the end effector 300. End effector 300 includes a pair of jaw members, which include a cartridge assembly 308 and an anvil 306. Cartridge assembly 308 houses one or more fasteners 433 (FIG. 13 ) that are disposed therewithin and is configured to deploy the fasteners 433 upon firing of instrument 100. The anvil 306 is movably (e.g., pivotally) mounted to the end effector 300 and is movable between an open position, spaced apart from cartridge assembly 308, and a closed position wherein anvil 306 is in close cooperative alignment with cartridge assembly 308, to thereby clamp tissue.

Referring to FIG. 13 , a disassembled view of the end effector 300 is shown. The end effector 300 also includes a carrier 431 having an elongate channel 411, a base 412 and two parallel upstanding walls 414 and 416 which include several mounting structures, such as notches 439, for supporting the cartridge assembly 308 and the anvil 306. A longitudinal slot 413 extends through the elongate channel 411.

The carrier 431 also includes a plate cover 415 disposed on a bottom surface thereof. The plate cover 415 is configured to frictionally engage with channel 411 of the carrier 431 and functions to protect tissue from moving parts along the exterior of carrier 431. The carrier 431 also includes a pair of tabs 407 and 409 disposed at a proximal end of respective walls 414, 416, and being configured for coupling to a housing portion 410 of end effector 300.

The carrier 431 also includes a holder plate 402 disposed on a top surface thereof. The holder plate 402 is configured to frictionally engage the carrier 431 and the cartridge assembly 308 to secure the fasteners 433 and pushers 437 therein. The holder plate 402 includes a pair of distal wings 402 a and a pair of proximal wings 402 b configured to engage distal tabs 436 a and proximal tabs 436 b of the cartridge assembly 308, respectively. The distal wings 402 a of the holder plate 402 are also configured and dimensioned to engage slots 439 a disposed at a distal end of the carrier 431 thereby securing the cartridge assembly 308 to the carrier 431.

With continuing reference to FIG. 13 , the distal portion of channel 411 supports the cartridge assembly 308 which contains the plurality of surgical fasteners 433 and a plurality of corresponding ejectors or pushers 437. End effector 300 includes an actuation sled 440 having upstanding cam wedges 444 configured to exert a fastener driving force on the pushers 437, which drive the fasteners 433 from cartridge assembly 308, as described in more detail below. Cartridge assembly 308 is maintained within channel 411 by lateral struts 436 which frictionally engage corresponding notches 439 formed in the upper surfaces of channel walls 414 and 416. These structures serve to restrict lateral, longitudinal, and elevational movement of the cartridge assembly 308 within channel 411. In any of the embodiments disclosed herein, the cartridge assembly 308 can be removable and replaceable so that the end effector 300 can be reused within a particular surgery allowing for multiple firings of a single end effector 300.

A plurality of spaced apart longitudinal slots (not shown) extend through cartridge assembly 308 and accommodate the upstanding cam wedges 444 of actuation sled 440. The slots communicate with a plurality of pockets 442 within which the plurality of fasteners 433 and pushers 437 are respectively supported. The pushers 437 are secured by a pusher retainer (not shown) disposed below the cartridge assembly 308, which supports and aligns the pushers 437 prior to engagement thereof by the actuation sled 440. During operation, as actuation sled 440 translates through cartridge assembly 308, the angled leading edges of cam wedges 444 sequentially contact pushers 437 causing the pushers to translate vertically within slots 446, urging the fasteners 306 therefrom. The cartridge assembly 308 also includes a longitudinal slot 485 to allow for a knife blade 474 to travel therethrough, as described in more detail below.

With continuing reference to FIGS. 13 and 14 , the end effector 300 includes an anvil cover 435 disposed over the anvil 306. The anvil cover 435 protects tissue from moving parts along the exterior of anvil 306. The anvil cover 435 includes opposed mounting wings 450 and 452 which are dimensioned and configured to engage detents 454 and 456 of the anvil 306, respectively. The mounting wings 450 and 452 function to align the anvil 306 with the cartridge assembly 308 during closure. The anvil 306 and the cover 435 are configured to remain in an open configuration until closed, as described in more detail below.

The anvil 306 is pivotally coupled to the carrier 431. The carrier 431 includes a pair of openings 421 and 422 formed in respective tabs 407, 409. The anvil cover 435 also includes a pair of opposed openings 457 and 459 found therein. A pivot pin 417, or a pair of pins, passes through the openings 421, 422, 457, and 459 allowing for pivotal coupling of the anvil 306 to the carrier 431 and the cartridge assembly 308.

As seen in FIGS. 13 and 14 , end effector 300 further includes an axial drive screw 460 for transmitting the rotational drive forces exerted by the second drive shaft 220 a, as described in further detail below, to actuation sled 440 during a stapling procedure. Drive screw 460 is rotatably supported in carrier 431 and includes a threaded portion 460 a and a proximal engagement portion 460 b. The drive screw 460 is rotatably secured by a thrust plate 410 b within the distal housing member 410 such that the drive screw 460 may be rotated relative to the carrier 431. Distal housing member 410 of the end effector 300 is coupled to the proximal end of the carrier 431 via pivot pin 417. The housing member 410 includes a bore 414 (FIG. 14 ) defined therethrough that houses the engagement portion 460 b therein. The distal tip of the drive screw 460 rests in a recess defined in the channel 411 of the carrier 431.

As shown in FIGS. 13-15 , the drive screw 460 is coupled to a drive linkage 600, which mechanically engages the second drive shaft 220 a, as described in further detail below, and the drive screw 460 of end effector 300. The drive linkage 600, disposed within the housing portion 410, is off-axis with respect to the drive screw 460. In particular, the longitudinal axis defined by the drive linkage 600 is at a non-parallel (e.g., non-zero angle) angle with respect to a longitudinal axis defined by the drive screw 460. In embodiments, the drive linkage 600 may be disposed along the same longitudinal axis as the drive screw 460.

With reference to FIG. 15 , the drive linkage 600 includes a proximal engagement portion 601 and a distal engagement portion 603. The proximal engagement portion 601 is configured to be engaged by a coupling member 515, and the distal engagement portion 603 is dimensioned and configured to engage the proximal engagement portion 460 b of drive screw 460. In particular, the engagement portion 601 includes a faceted surface, which is configured and dimensioned to interface with a socket 516 of the coupling member 515, which has a corresponding faceted surface. The engagement portion 603 also includes a faceted surface, which is configured and dimensioned to interface with a socket 460 c of the engagement portion 460 b, which has a corresponding faceted surface. The mechanical coupling of the engagement portions 601 and 603 with the sockets 516 and 460 c, respectively, occurs via abutment of the male faceted surfaces of the engagement portions 601 and 603 with corresponding female faceted socket 516 and 460 c, which allows for transfer of rotational motion of the coupling member 515 to the drive linkage 600 and, in turn, to the drive screw 460. In embodiments, the drive linkage 600 may mechanically interface with the drive screw 460 and the coupling member 515 using any other suitable mechanical coupling, e.g., pinned.

With reference to FIGS. 13 and 14 , end effector 300 further includes a drive beam 462 disposed within carrier 431. The drive beam 462 includes a vertical support strut 472 and an abutment surface 476, which engages the knife blade 474, which in turn, engages the actuation sled 440. The drive beam 462 also includes a cam member 480 disposed on top of the vertical support strut 472. Cam member 480 is dimensioned and configured to engage and translate with respect to an exterior camming surface 482 of anvil 306 to progressively clamp the anvil 306 against body tissue during firing.

A longitudinal slot 484 extends through the anvil 306 to accommodate the translation of the vertical strut 472. This allows the cam member 480 to travel in between the cover 435 and anvil 306 during firing. In embodiments, the anvil cover 435 may also include a corresponding longitudinal slot (not shown) formed on an underside thereof and is secured to an upper surface of anvil 306 to form a channel therebetween.

The drive beam 462 includes a retention portion 488 having a threaded bore 489 defined therethrough. The drive screw 460 is threadably coupled to the retention portion 480 through the bore 489, such that as the drive screw 460 is rotated, the drive beam 462 travels in a longitudinal direction along the longitudinal axis defined by the drive screw 460.

In use, as the drive screw 460 is rotated in a clock-wise direction, the drive beam 462 travels in a distal direction closing the anvil 306 as the cam member 480 pushes down on the camming surface 482 thereof. The drive beam 462 also pushes the sled 440 in the distal direction, which then engages the pushers 437 via the cam wedges 444 to eject the fasteners 433. The drive beam 462 may be made of any suitable first material including, but not limited to, plastics, metals, and combinations thereof. The first and second materials may be either same or different.

The knife blade 474 travels slightly behind actuation sled 440 during a stapling procedure to form an incision between the rows of fastener body tissue. As the drive beam 462 is driven in the distal direction, the abutment surface 476 of the vertical strut 472 pushes the knife blade 474, which then pushes sled 440 in the distal direction to eject the fasteners 433 and simultaneously dissect tissue with the knife blade 474. The knife blade 474 and the drive beam 462 travel through the longitudinal slots 484 and 485. The drive beam 462 closes the anvil as it is driven in the distal direction and also pushes the sled 440, which, in turn, ejects the fasteners 433 ahead of the knife blade 474. As the fasteners 433 are ejected they are deformed again the tissue-contacting (e.g., underside) surface of the anvil 306 having a plurality of anvil pockets (not shown).

With reference to FIGS. 11, 12, and 14-17A, the articulating assembly 230 is shown. The assembly 230 includes a distal joint member 232 for coupling to a proximal end of the end effector 300 and a proximal joint member 234 coupled to the distal end 210 b of the body portion 210.

With reference to FIGS. 13 and 16-21 the housing portion 410 of the end effector 300 includes one or more posts 410 a for insertion into one or more corresponding bores 580 a within a socket 580. The socket 580 is rotationally disposed within the joint member 232. In particular, the socket 580 is disposed within a spacer 232 a and includes a textured ring 232 b disposed on an outer surface thereof. This allows the socket 580 to be rotated about the longitudinal axis “C-C” (FIG. 12 ) by a shaft 513 that is longitudinally arranged within the joint member 232, as described in further detail below.

The shaft 513 includes one or more facets 513 a such that the shaft 513 is keyed to a central bore 580 b of the socket 580. This allows for rotation of the socket 580 along with the shaft 513. As shown in FIG. 16 , during insertion the proximal engagement portion 601 of the drive linkage 600 also engages the socket 516 of the coupling member 515, which actuates the drive screw 460 as described in further detail below.

With reference to FIGS. 17A-19 , the proximal joint member 234 and the distal joint member 232 are configured and dimensioned as a clevis to interface with a pin 505. The pin 505 includes one or more longitudinal facets 505 a along at least a portion of the pin 505. The proximal joint member 234 of the neck assembly 230 includes a pair of opposing arms 235, 237 including a pair of opposing circular bores 235 a, 237 a, respectively, allowing the pin 505 to be rotationally coupled within the bores 235 a, 237 a of opposing arms 235, 237. With reference to FIGS. 17A-B, the joint member 232 of the assembly 230 also includes a pair of opposing arms 239, 241 including a pair of opposing bores 239 a, 241 a. With reference to FIG. 17B, each of the bores 239 a, 241 a includes a facet 239 b, 241 b, such that when the pin 505 is inserted into the bores 235 a, 237 a, 239 b, 241 b, the pin 505 can rotate freely within the bores 235 a, 237 a. This secures the joint member 232 to the pin 505 about the bores 239 a, 241 a via mating of the facet 505 a of the pin 505 with the facets 239 b, and 241 b. Since the pin 505 is keyed to the bores 239 a, 241 a of the joint member 232 and is free-floating within the bores 235 a, 237 a of the proximal joint member 234, the joint member 232 along with the end effector 300 may be freely rotated with respect to the proximal joint member 234 about a articulation axis “B-B” (FIG. 12 ) defined by the pin 505 as shown in FIG. 22 and described in further detail below.

With reference to FIGS. 17A and 18 , the assembly 230 also includes the second (e.g., actuating/firing) drive shaft 220 a, which may be axially rotatable within the body portion 210. The drive shaft 220 a includes a second gear element 502 coupled thereto and configured to rotate therewith about a longitudinal axis defined by the drive shaft 220 a. The gear element 502 is meshingly engaged with a first transfer gear element 504. The gear element 504 is held in position by the pin 505 and is configured to rotate about the pin 505.

The gear element 504 is also meshingly engaged with a gear element 506 within the joint member 232. The gear elements 502, 504, 506 are bevel gears allowing for meshing engagement thereof even as the joint member 232 and the end effector 300 are pivoted with respect to the body portion 210. The gear element 502 rotates about a longitudinal axis parallel with the axis “A-A.” The gear element 504 rotates about the axis “B-B” (FIG. 12 ) and the gear element 506 rotates about a longitudinal axis parallel with the axis “C-C” (FIGS. 2 and 10 ). The gear element 506 is connected to a gear element 510 by a shaft 508. The gear element 506, the gear element 510, and the shaft 508 rotate within the joint member 232 about a longitudinal axis defined by the central axis of the shaft 508. The gear element 510 is, in turn, meshingly engaged with a gear element 512 that rotates about the shaft 513 that is longitudinally arranged within the joint member 232. The gear element 512 is meshingly engaged with a gear element 514 of the coupling member 515. The coupling member 515 includes a shaft portion that extends distally to the socket 516, which is coupled to drive linkage 600 as described above. Rotation of the drive shaft 220 a results in rotation of the gear elements 502, 504, 506, 510, 512, 514 and the socket 516, which in turn, rotates the drive screw 460 via the drive linkage 600 thereby actuating the firing process as described above.

With continued reference to FIGS. 16-21 , the assembly 230 also includes the third (e.g., rotating) drive shaft 222 a, which may be axially rotatable within the body portion 210. The drive shaft 222 a includes a third gear element 552 coupled thereto and configured to rotate therewith about a longitudinal axis defined by the drive shaft 222 a. The gear element 552 is meshingly engaged with a second transfer gear element 554. The gear element 554 is held in position by the pin 505 and is configured to rotate about the pin 505.

The gear element 554 is also meshingly engaged with a gear element 556 within the joint member 232. The gear elements 552, 554, 556 are bevel gears allowing for meshing engagement thereof even as the joint member 232 and the end effector 300 are pivoted with respect to the body portion 210. The gear element 552 rotates about a longitudinal axis parallel with the axis “A-A.” The gear element 554 rotates about the axis “B-B” and the gear element 556 rotates about a longitudinal axis parallel with the axis “C-C.” Use of the bevel gears, namely, the gear elements 502, 504, 506, 552, 554, 556, allows for tightest possible 90° bend angle of the joint member 232 during articulation with respect to the body portion 210 of the adapter assembly 200 as shown in FIG. 23 , which shows the joint member 232 pivoted with respect to the joint member 234.

With continued reference to FIGS. 16-21 , the gear element 556 is connected to a gear element 560 by a shaft 558. The gear element 556, the gear element 560, and the shaft 558 rotate within the joint member 232 about a longitudinal axis defined by the central axis of the shaft 558. The gear element 560 is, in turn, meshingly engaged with a gear element 562, which is fixedly coupled to the shaft 513, such that rotation of the gear element 562 results in rotation of the shaft 513. As described above, the socket 580 is securedly coupled to the shaft 513, such that as the shaft 513 is rotated in either clockwise or counterclockwise direction about the longitudinal axis “C-C” the socket 580 is also rotated in the same direction. Since the end effector 300 is engaged with the socket 580 as described above, the end effector 300 is similarly rotated by the shaft 513. The end effector 300 is configured to rotate about its own longitudinal axis in this manner.

The present disclosure also provides for a rotation lockout assembly 700 for preventing rotation of the end effector 300 during firing. This allows for prevention of tissue damage due to the torque generated during the firing process which would otherwise backfeed the gears within the neck assembly 230 and inadvertently rotate the end effector.

With reference to FIGS. 13, 15, and 17A, the housing 410 may include a distal portion 427 a and a proximal portion 427 b interconnected by a bolt 429 with the bore 423 a (FIG. 13 ) defined therethrough. The shaft 513 disposed within the joint member 232 includes a bore 423 b (FIG. 17A) defined therethrough. The bores 423 a and 423 b are in longitudinal alignment.

With reference to FIGS. 15-17A, the lockout assembly 700 includes a push rod 702 disposed within the bore 423 a and a locking member 704 disposed within the joint member 232. The locking member 704 includes a rod 706 disposed within the bore 423 b. The distal end of the rod 706 is in contact with a proximal end of the push rod 702, such that longitudinal movement of either the push rod 702 or the locking member 704 is translated therebetween. The locking member 704 also includes one or more lock lugs 707 configured and dimensioned to meshingly engage the gear element 562. The locking mechanism 700 also includes a spring 708, which is coupled to the joint member 232 and pushes the locking member 704 in a distal direction.

With reference to FIG. 16 , prior to insertion of the end effector 300 into the joint member 232, the locking member 704 is engaged with the lock lug 707 thereof preventing actuation of the coupling member 515. As shown in FIGS. 15 and 18 , after insertion of the end effector 300, the drive beam 462 is in its proximal most position since it has not been fired and therefore abuts the distal end of the push rod 702. This moves the push rod 702 proximally, which also moves the locking member 704 in a proximal direction to disengage the lock lug 707 from the teeth of the gear element 562. The disengagement of the locking member 704 allows for rotation of the shaft 513, the socket 580, and in turn, the end effector 300 in either clockwise or counterclockwise direction about the longitudinal axis “C-C.”

Once the desired rotational position is achieved firing may be commenced as described above. Firing moves the drive beam 462 distally, which allows the push rod 702 along with the locking member 704 to travel distally due to the biasing forces of the spring 708 as shown in FIG. 24 . This moves the lock lug 707 of the locking member 704 into engagement with the gear element 562 preventing rotation of the end effector 300 during the firing process.

With reference to FIGS. 17A, 18 and 25-27 , the assembly also includes the first (e.g., pivoting) drive shaft 218 a, which may be axially rotatable within the body portion 210. The drive shaft 218 a includes a first gear element 570 at its distal end, which is configured as a worm gear. The gear element 570 is meshingly engaged with a pivoting gear element 572, which is configured as a worm wheel drive. The gear element 572 includes a bore 574 a therethrough having a facet 574 b. The gear element 572 is disposed between the gear elements 504, 554 and is secured to the pin 505 about the bore 574 a via mating of the facet 505 a of the pin 505 with the facet 574 b of bore 574 a of gear element 572 in a keyed relationship. Thus, the gear element 572 is secured to the pin 505 along with the joint member 232, which allows for rotation of the joint member 232 along with the end effector 300 with respect to the body portion 210 about the articulation axis “B-B” defined by the pin 505 as described in further detail below.

As shown in FIGS. 25-27 , articulation of the joint member 232 about the articulation axis “B-B” is imparted by rotation of the drive shaft 218 a about its longitudinal axis and simultaneous longitudinal movement of the drive shaft 218 a along its longitudinal axis, which in turn, rotates the gear element 572 via the gear element 570. Simultaneous rotational and longitudinal movement of the drive shaft 218 a may be accomplished via a complementary worm gear mechanism at its proximal end. Since the gear element 572 is securedly coupled to the pin 505, rotation of the gear element 572 rotates the pin 505 and the joint member 232, which is also securedly coupled thereto as described above. The drive shaft 218 a includes a thrust plate 218 b that acts as a stop member preventing longitudinal movement of the drive shaft 218 a beyond a certain point, which in turn, prevents rotation of the joint member 232 and the end effector 300 beyond a desired stopping point. In embodiments, the joint member 232 may be rotated about the articulation axis “B-B” up to about 300°, with about 150° in either direction from the first aligned position in which the second longitudinal axis “C-C” is substantially aligned with the first longitudinal axis “A-A.” In further embodiments, the joint member 232 may be rotated about the articulation axis “B-B” up to about 180°, with about 90° in either direction from the first aligned position.

The gearing relationship between the gear elements 570 and 572 allows for precise pivoting of the end effector 300 with respect to the adapter assembly 200. In addition, the gear elements 570 and 572 provide for a gearing reduction due to a worm gear/worm wheel drive relationship, thereby obviating the need for additional gear reduction mechanisms at the proximal end of the adapter assembly 200.

Referring to FIGS. 28-30 , another embodiment of an articulating assembly 1230 provided in accordance with the present disclosure including a longitudinally translating drive shaft 1218 a. Articulating assembly 1230 is substantially similar to articulating assembly 230 and includes most of the components of articulating assembly 230, which are not described below to avoid repetition. Drive shaft 1218 a is operatively disposed within body portion 210. Drive shaft 1218 a includes a first gear element 1570 that engages pivoting gear element 572. In embodiments, gear element 1570 may be configured as a toothed rack that engages pivoting gear element 572 in a rack and pinion relationship, as best illustrated in FIG. 30 .

With reference to FIGS. 31-33 , articulation of joint member 232 about articulation axis “B-B” (FIG. 28 ) is imparted by longitudinal translation of drive shaft 1218 a along its longitudinal axis, which is parallel to the longitudinal axis “A-A” (FIG. 10 ). Longitudinal movement of drive shaft 1218 a, in turn, rotates pivoting gear element 572 via first gear element 1570. The longitudinal translation of drive shaft 1218 a may be accomplished via a drive mechanism described above with respect to drive shaft 218 a. First gear element 1570 may extend along drive shaft 1218 a such that a portion of first gear element 1570 is adjacent a proximal end of drive shaft 1218 a. Since pivoting gear element 572 is securely coupled to pin 505, rotation of pivoting gear element 572 rotates pin 505 and joint member 232, which is also securely coupled thereto as described above.

Drive shaft 1218 a also includes a thrust plate 1218 b that acts as a stop member preventing longitudinal translation of drive shaft 1218 a beyond certain limits (e.g., a proximal limit 1219 a or a distal limit 1219 b), which in turn, prevents rotation of joint member 232 and end effector 300 beyond a desired point. In embodiments, joint member 232 may be pivoted about the articulation axis “B-B” to a first and second pivoted positions in either direction from a first aligned position in which the second longitudinal axis “C-C” (FIG. 28 ) is substantially aligned with the first longitudinal axis “A-A” (FIG. 10 ). The first and second pivoted positions may be up to about 300°, with about 150° of pivot in either direction from the first aligned position. In further embodiments, joint member 232 may be pivoted about the articulation axis “B-B” up to about 180°, with about 90° of pivot in either direction from the first aligned position.

The gearing relationship between gear elements 1570 and 572 allows for precise pivoting of end effector 300 with respect to adapter assembly 200. In addition, the interaction of gear elements 1570 and 572 may provide for a back drive mechanism that permits external forces exerted on an end effector attached to articulating neck assembly 1230 about the pivot axis to back drive the motor until a solid stop is reached (i.e., thrust plate 1218 b reaching proximal or distal limit 1219 a, 1219 b). The solid stop may correspond to the first or second rotated positions of end effector 300. The back drive mechanism may also include a force multiplier configured to reduce the force exerted on the motor by the back drive mechanism. The force multiplier may be from about 1 to about 40, in embodiments, from about 5 to about 20.

In the examples discussed above, the hand-held instrument handle housed a removable and replaceable and/or rechargeable battery, as well as a motor and computer and memory components. A removable and replaceable adapter assembly corresponds to one or more end effector configurations, the end effectors being removable and replaceable. For example, an adapter is configured for use with circular stapling reload end effectors in various sizes, and with or without various other features such as suction and irrigation, visualization, etc. Other adapters are available for use with linear surgical stapling reloads come in various sizes, configurations, possibly having other features such as dissection tips and/or pre-loaded surgical buttress material. In the examples above, the handle may be disposable, for single-procedure use, or sterilizable and re-used for a prescribed number of procedures.

In another example shown in FIG. 34 , a surgical stapling handle 2010 contains a removable and re-usable motor and battery (not shown), and the handle housing 2012 itself opens and closes to receive those components. This may extend the useful life of the motor, which can be housed in the handle housing in a sealed fashion, avoiding the need to sterilize the motor, the battery, etc. The handle housing 2012 is openable like a shell, as shown and is re-sterilizable. The handle housing carries a series of buttons 2014 and controls for actuating articulation, clamping of tissue, stapling of tissue and cutting of the tissue. These buttons, as well as various indicators (such as lights, screens and the like) can be as discussed above or similar thereto. The controller desirably contains a microprocessor and memory components that record information concerning the use of the instrument and can interact with sensor provided in the other components such as the end effector reload, adapter, staple cartridge assembly, etc.

It is contemplated that the adapter assembly 2016 can be removable, as mentioned above, or it can be permanently attached to the handle. The adapter assembly includes a drive mechanism which has mechanical components for manipulating the end effector (FIG. 34A), such as articulation, opening and closing of jaws, etc. As shown in FIG. 35 , the adapter assembly 2016 has a proximal end 2018 with a knob 2020, and a distal end 2022 that can be attached to a surgical stapling end effector reload 3010. The proximal end 2018 has a lead screw 2026 with a proximal end 2028 that is accessible at the proximal end 2018 of the adapter assembly 2016. An inner tube 2030 is threadably engaged with (i.e., it has helical grooves) the lead screw, which also has helical threads so that rotation of the lead screw 2026 will translate the inner tube 2030 in a proximal or distal direction. There is a thrust bearing 2032 (FIG. 36 ) at the proximal end of the lead screw so that it is mounted in the knob 2020. A pusher 2034 is attached to the distal end 2026 a of the lead screw and is connected to a bar 2036 through a pin, screw, or the like. The inner tube 2030, thrust bearing 2032, and pusher 2034 can also be seen in FIGS. 39A and 39B

The adapter assembly has a drive mechanism inside an elongate shaft that articulates. As shown in FIG. 37 , the distal end 2022 of the adapter assembly 2016 has a pair of bar guides 2038, one each on either side of a bar 2036, and adjacent to the bar guides is a pair of blowout plates 2046 that are next to the bar guides, but distal to them. The bar itself is made of a plurality of layers, or stainless steel or equivalent material, that are stacked against one another. At a distal end 2040 of the bar, a beam is attached to the bar. The beam shown is an I-beam 2042 having an upper flange 2042 a and a lower flange 2042 b is attached. The bar is further supported by a support block 2044 that has an opening 2046 so that it surrounds the bar, and the blowout plates 2046. The support block is curved in shape, with the convex side of the support block facing proximally, and is made of a strong material like stainless steel. As seen in FIG. 37 , the blowout plates each have a distal end 2046 a that form a flange 2048 for being received in a slot in a mounting member 2050. The mounting member 2050 forms the distal end of the adapter assembly 2016 and can be attached to the end effector reload. The mounting member 2050 also has an arcuate slot for receiving and supporting the support block 2044, and also allowing the support block 2044 to move so that the assembly (the bar, blowout plates, support block) move off-center with respect to the adapter assembly when the end effector reload is articulated and pivoted with respect to the adapter (see FIG. 38 ). In such movement, the bar guides 2038 are moved as well (see FIG. 39 ). The bar, the pair of bar guides, the pair of blowout plates, and the support block are pivotable from a central position in the adapter assembly to an off-center position in the adapter assembly.

When the device is articulated, the distal ends of the bar guides pivot off-center, supporting the blowout plates and the plurality of layers forming the bar. When the guides pivot off-center, it creates a large radius for the bar to be driven through, reducing stress on the bar, and the layers making up the bar. The bar guides are separate members, but they pivot together. The assembly works in the same way when articulated in the opposite direction.

I-beam 2042 and bar 2036 are moved by the inner tube 2030 in a distal direction to effect the closing of the end effector jaw members onto tissue, and to fire staples and cut tissue. (FIGS. 39A and 39B). The end effector reload 3010 has an anvil assembly 3012, a cartridge assembly 3014, and a channel 3016 for receiving the cartridge assembly. The entire end effector reload 3010 can be attached to the adapter assembly 2016, and removed and replaced after use. (FIG. 46 ). Another end effector 3010 can be re-attached, and/or a different end effector, such as a dissecting tip end effector reload, for example, can be attached to adapter assembly 2016. The anvil assembly 3012 can be one or more parts machined and/or welded together, and having an anvil plate 3012 a with recesses shaped for forming the staples into a closed shape when they are driven against the anvil plate 3012 a. The staple cartridge assembly 3014 is attached to the channel 3016 and has an upper surface with slots (also seen in FIG. 50 ) that house the unformed staples and allow their ejection from the cartridge assembly 3014 and into tissue.

The anvil assembly 3012, staple cartridge assembly 3014, and channel 3016 have slots that allow the passage of the I-beam 2042 and bar 2036. The layers of the bar 2036 are dimensioned so that they extend into both the slot in the anvil assembly 3012 and the slot in the channel 3016. The staple cartridge assembly 3014 has a sled 3018 that carries a knife 3020 rotatably supported on the sled. The knife can be biased in an upward position for cutting tissue, or it can be biased in a downward position where it does not access tissue, and/or the knife 3020 can be moved by a feature on the I-beam 2042. As shown in FIG. 40 , the feature of the I-beam can be a slot 3022 for camming a protrusion 3024 on the knife 3020. When the bar and I-beam are moved distally, the engagement of the flanges 2042 a and 2042 b of the I-beam with the anvil assembly and channel move the anvil assembly, staple cartridge assembly, and channel into approximation to engage tissue. In further movement distally, the I-beam 2042 pushes the sled 3018 and knife 3020 distally. (See FIGS. 40 and 40A; see also a substantially similar embodiment described in greater detail below and illustrated in at least FIGS. 52-63 ). The sled interacts with pushers in the staple cartridge assembly to drive the staples out of the slots. In other examples, the knife can be formed directly on the I-beam 2042.

The proximal end 3030 a of the articulation mechanism 3030 of the adapter assembly 2016 is shown in FIG. 41 . A cylindrical articulation nut 3032 having threads on its proximal end 3034. An input shaft 3036 with corresponding threads is enmeshed with the threads of the nut 3032. The rotating shaft 3036 will rotate the nut 3032 through the operation of the threads. The interior of the nut 3032 is hollow and also has a helical groove 3038. The groove 3038 is engaged with a groove 3040 on the outside of a screw 3042 (FIG. 42 ) disposed inside the nut 3032. When the nut 3032 rotates, the screw moves distally or proximally, to move an articulation link 3044. In this way, distal movement of the link will articulate or pivot the end effector in one direction, and proximal movement of the link 3044 will articulate or pivot the end effector in the other direction.

The distal end 3030 b of the articulation mechanism 3030 of the adapter assembly 2016 is shown in FIG. 43 . The articulation link 3044 ends in a connection to a second link which is a short link 3048, via a pin. The short link is curved and also pinned to the mounting member 2050 at an off-center location. (FIG. 44 ). The mounting member 2050 is connected to the adapter assembly 2016 at a pin 3050 a and the mounting member 2050 pivots about the pin 3050 when the links 3044, 3048 are moved. (See FIGS. 44 and 45 ).

The adapter assembly 2016 proximal end 2018 knob 2020 houses a mechanism for rotating the entire adapter assembly about its own longitudinal axis “A”. A rotation input shaft 3052 rotates a gear 3054 that is enmeshed with a ring gear 3055. When the input shaft rotates, it rotates the knob 2020, outer tube 2021, and everything attached to it. (FIG. 45A).

FIG. 46 shows the attachment of the end effector reload 3010 to the adapter assembly. The anvil assembly 3012 has a semi-cylindrical proximal end 3012 a that forms tissue stops 3060. The tissue stops 3060 form walls, one on each side of the reload 3010. On an interior surface of each tissue stop 3060 a locking tab 3062 is defined. The locking tabs each have an extension 3062 a that is received in a connection feature of the mounting member. The connection feature of the mounting member is a pair of keyways 2051 defined in the mounting member 2050. (FIGS. 46, 47, 48 ). The keyways each form a slot that receives the extension 3062 a to lock the reload onto the adapter assembly. The keyways slots are upwardly open, so that the end effector reload is locked onto the adapter assembly through movement of the reload downwardly. (FIGS. 47 and 48 ). Spring fingers 2051 a engage the locking tab extensions. (FIG. 48A).

The example described above has a staple cartridge assembly that is not intended to be removed and replaced in the end effector reload 3010. In further examples, the adapter assembly 2016 and end effector reload 3010 are as described above, except that the end effector reload has a removable and replaceable staple cartridge assembly. As shown in FIGS. 49 and 50 , the staple cartridge assembly 3014″ has a snap-fit arrangement at its proximal end, formed by a rearward-facing opening 3014 a″ in the staple cartridge body 4015 and a corresponding opening 3018 a″ in the support tray. These openings engage a boss 3016 a″ in the channel 3016″ in a snap-fit relationship. In this way, the end effector reload, adapter assembly, and stapler handle can be reused to fire another set of staples, without replacing the end effector reload. As the length of the staple lines depends on the selection of the end effector reload, that component must be replaced to change the length of the staple lines formed in tissue. However, the size of the staples, and the arrangement of staples (more than one staple size, or all the same size staples), whether there is a pre-loaded buttress or curved tip or other feature, can be changed by changing the selection of the staple cartridge assembly 3014″. A manually actuated stapler handle, in an instrument having a removable and replaceable staple cartridge assembly, is disclosed in U.S. Pat. No. 9,016,539, the entire disclosure of which is hereby incorporated by reference herein.

In a further alternative example of an articulation mechanism in the adapter assembly, FIG. 51 shows an articulation mechanism having a threaded engagement in the distal portion of the adapter assembly 4016. The articulation mechanism is as described above, and has an articulation link 4044, and a short link 4048, connected to one another by a pin 4046. The drive shaft 4049 extends to the distal end of the adapter assembly 4016 and forms a series of threads 4050 on its distal end. The threads 4050 are engaged with threads on the articulation link and are used to translate the articulation link 4044 when the drive shaft 4049 rotates.

Turning now to FIGS. 52-63 , another embodiment of an end effector is generally referred to as end effector 5000. End effector 5000 includes a tool assembly 5100 (e.g., a multi-use loading unit or MULU) and a cartridge assembly 5200 that mounts to tool assembly 5100. Similar to tool assembly 304 above, tool assembly 5100 generally includes a first jaw member 5110 and a second jaw member 5112 that are pivotally coupled together. Second jaw member 5112 supports cartridge assembly 5200, which may be selectively replaceable, a lead screw 5114, and an I-beam 5116 (see FIG. 61 ) that is threadably coupled to lead screw 5114 to selectively advance I-beam 5116 along cartridge assembly 5200 for approximating first and second jaw members 5110, 5112 and/or firing end effector 5000. End effector 5000 is configured to couple to an adapter assembly 200 x that selectively couples to surgical instrument 100 (see FIG. 52A).

With reference to FIG. 54 , cartridge assembly 5200 of end effector 5000 includes a cartridge holder 5210 and a cartridge 5220 having a tissue-contacting surface 5222. Cartridge holder 5210 and cartridge 5220 of cartridge assembly 5200 support pushers 5230, fasteners 5240 supported on pushers 5230, and a sled assembly 5250 that is slidably advanceable along cartridge assembly 5200 to fire fasteners 5240 from cartridge 5220 as pushers 5230 cam along sled assembly 5250.

As seen in FIGS. 55-59 , sled assembly 5250 includes an actuation sled 5252 and a knife assembly 5254 pivotally supported on actuation sled 5252 between a first position and a second position. Actuation sled 5252 includes a plurality of upstanding cam wedges 5252 a separated by a knife mount 5252 b and configured to exert a fastener driving force on pushers 5230 (FIG. 54 ). Knife mount 5252 b defines a spring bore 5252 c and a vertical channel 5252 d therein. Knife mount 5252 b further includes a pivot pin 5252 e that extends transversely from a sidewall 5252 f of knife mount 5252 b to pivotally support knife assembly 5254 thereon, a stabilizing finger 5252 g that extends proximally from knife mount 5252 b and is positioned to provide lateral stability to knife assembly 5254 when the knife assembly 5254 is disposed in the second position, and a blocking arm 5252 h that extends over knife assembly 5254 and is positioned to support knife assembly 5254 in the second position to facilitate tissue cutting. Knife assembly 5254 includes a spring 5254 a (e.g., compression spring) that is received within spring bore 5252 c of knife mount 5252 b, and a knife 5254 b engaged with spring 5254 a. As indicated by arrow “A,” knife 5254 b of knife assembly 5254 is pivotally supported on pivot pin 5252 e to enable knife 5254 b to pivot (e.g., rotate) about pivot pin 5252 e between a first position (FIG. 55 ), in which knife 5254 b is disposed below tissue-contacting surface 5222 of cartridge 5220 to prevent tissue cutting, and a second position (FIG. 56 ), in which knife 5254 b is raised above tissue-contacting surface 5222 of cartridge 5220 to enable tissue cutting for tissue supported on tissue-contacting surface 5222.

Knife 5254 b of knife assembly 5254 includes a knife arm 5254 c that supports a blade 5254 d on a knife head 5254 x disposed a proximal end portion of knife 5254 b. Knife 5254 b further defines a pivot hole 5254 e on a distal end portion thereof that receives the pivot pin 5252 e of knife mount 5252 b. Knife arm 5254 c includes an arched configuration and is positioned to engage a bottom surface of blocking arm 5252 h of knife mount 5252 b to prevent knife 5254 b from pivoting beyond the second position of knife 5254 b. Knife arm 5254 c further includes a distal foot 5254 f that engages spring 5254 a to enable spring 5254 a to urge knife 5254 b toward the first position in which blade 5254 d of knife 5254 b is positioned below blocking arm 5252 h of knife mount 5252 b (see FIG. 57 ). Distal foot 5254 f includes an arch 5254 g along which a distal portion of spring 5254 a cams as knife 5254 b pivots about pivot pin 5252 e. Spring 5254 a of knife assembly 5254 is positioned to urge distal foot 5254 f distally to maintain knife 5254 b in the first position (e.g., so that blade 5254 d remains below tissue-contacting surface 5222 of cartridge 5220). Distal foot 5254 f further includes a proximal toe 5254 h that is receivable in vertical channel 5252 d of knife mount 5252 b as knife 5254 b pivots relative to knife mount 5252 b from the first position to the second position.

In operation, illustrated in FIGS. 60-63 , I-beam 5116 is advanced between first and second jaw members 5110, 5112 to approximate or clamp first and second jaw members 5110, 5112 together (see FIG. 60 ). In such clamped position, a distal surface 5116 a of I-beam 5116 is spaced from a proximal surface 5252 x of actuation sled 5252 of sled assembly 5250, and knife head 5254 x of knife 5254 b of sled assembly 5250 is in contact with a camming surface 5116 b of I-beam 5116. As indicated by arrow “B,” when I-beam 5116 advances distally farther in response to rotation of lead screw 5114, as indicated by arrows “R,” knife head 5254 x of knife 5254 b of sled assembly 5250 cams upwardly along camming surface 5116 b of I-beam 5116 and against spring biasing forces imparted by spring 5254 a of knife assembly 5254. As knife head 5254 x cams along camming surface 5116 b of I-beam 5116, knife 5254 b pivots (e.g., rotates) upwardly and distally, as indicated by arrow “A,” from the first position toward the second position (see FIG. 62 ). As knife 5254 b of knife assembly 5254 moves toward the second position thereof, distal surface 5116 a of I-beam 5116 approximates proximal surface 5252 x of actuation sled 5252.

When knife 5254 b is in the second position thereof such that blade 5254 d of knife 5254 b is above tissue-contacting surface 5222 of cartridge 5220 and distal surface 5116 a of I-beam 5116 is in contact with proximal surface 5252 x of actuation sled 5252, further distal advancement of I-beam 5116 causes sled assembly 5250 to advance distally through cartridge assembly 5200, as indicated by arrow “C,” to fire end effector 5000 for forming fasteners 5240 and cutting tissue clamped by end effector 5000. Once fired, cartridge assembly 5200 can be removed and replaced for subsequent re-use of end effector 5000.

In some embodiments, knife head 5254 x of knife assembly 5254 may include a guide pin that extends transversely therefrom and that is configured to translate through a slot defined in, for example, an I-beam (see e.g., slot 3022 in FIG. 40 ) to facilitate pivoting movement of knife 5254 b (see e.g., FIGS. 40A and 40B which illustrate a similar embodiment with such a guide pin “GP”).

While persons skilled in the art will understand that the structures and methods specifically described herein and shown in the accompanying figures are non-limiting exemplary embodiments, and that the description, disclosure, and figures should be construed merely as exemplary of particular embodiments. It is to be understood, therefore, that the present disclosure is not limited to the precise embodiments described, and that various other changes and modifications may be effected by one skilled in the art without departing from the scope or spirit of the disclosure. For example, surgical instrument 100 and/or end effector 300 need not apply staples but rather may apply two part fasteners as is known in the art. Further, the length of the linear row of staples or fasteners may be modified to meet the requirements of a particular surgical procedure. Thus, the length of the linear row of staples and/or fasteners within a staple cartridge assembly may be varied accordingly. Additionally, the elements and features shown or described in connection with certain embodiments may be combined with the elements and features of certain other embodiments without departing from the scope of the present disclosure, and that such modifications and variations are also included within the scope of the present disclosure. Accordingly, the subject matter of the present disclosure is not limited by what has been particularly shown and described. 

What is claimed:
 1. A cartridge assembly for a surgical stapling system, the cartridge assembly comprising: a cartridge; a sled assembly configured to drive fasteners through the cartridge; a spring coupled to a coupling portion of the sled assembly; and a knife supported by the sled assembly and having a knife arm and a blade supported by the knife arm, the knife arm configured to pivot relative to the sled assembly about a pivot pin to move the blade between a first position and a second position, the knife arm including a foot that is in contact with the spring to enable the spring to urge the foot in a distal direction and the blade in the first position as the spring extends distally from the coupling portion of the sled assembly.
 2. The cartridge assembly of claim 1, wherein the blade is supported on a proximal portion of the knife arm.
 3. The cartridge assembly of claim 2, wherein the foot is distal to the blade and the spring.
 4. The cartridge assembly of claim 3, wherein the spring is a compression spring disposed in a substantially parallel relation with a longitudinal axis of the cartridge.
 5. The cartridge assembly of claim 4, wherein the sled assembly includes a knife mount that supports the spring, the knife mount coupled to the knife arm by the pivot pin.
 6. The cartridge assembly of claim 5, wherein the cartridge includes a tissue-contacting surface, wherein, in the first position, the blade has height that is disposed below the tissue-contacting surface.
 7. The cartridge assembly of claim 6, wherein the blade is aligned with the pivot pin when the blade is disposed in the first position.
 8. The cartridge assembly of claim 7, wherein, in the second position, the blade is disposed above the tissue-contacting surface.
 9. The cartridge assembly of claim 8, wherein the knife mount includes a stabilizing finger that extends from the knife mount to engage the knife arm when the blade is in the second position.
 10. The cartridge assembly of claim 9, wherein the stabilizing finger extends over at least one of the spring, the pivot pin, or the knife arm.
 11. A surgical stapling system, comprising: an end effector including an anvil assembly and a cartridge assembly, the cartridge assembly including: a cartridge having a tissue-contacting surface comprising openings of staple pockets; a sled assembly; a spring coupled to the sled assembly; and a knife arm pivotably supported on the sled assembly by a pivot pin, the knife arm including a foot that is coupled to the spring, the pivot pin disposed closer to the tissue contact surface than the spring; a blade supported on the knife arm and movable between a first position and a second position in response to pivoting movement of the knife arm.
 12. The surgical stapling system of claim 11, wherein the blade is supported on a proximal portion of the knife arm.
 13. The surgical stapling system of claim 12, wherein the foot is distal to the blade and the spring is positioned to urge the foot in the distal direction to maintain the blade in the first position.
 14. The surgical stapling system of claim 13, wherein the spring is a compression spring disposed in substantially parallel relation with a longitudinal axis of the cartridge.
 15. The surgical stapling system of claim 14, wherein the sled assembly includes a knife mount that supports the spring, the knife mount coupled to the knife arm by the pivot pin.
 16. The surgical stapling system of claim 15, wherein, in the first position, the blade has height that is disposed below the tissue-contacting surface.
 17. The surgical stapling system of claim 16, wherein the blade is aligned with the pivot pin when the blade is disposed in the first position.
 18. The surgical stapling system of claim 17, wherein, in the second position, the blade is disposed above the tissue-contacting surface and the pivot pin.
 19. The surgical stapling system of claim 18, wherein the knife mount includes a stabilizing finger that extends from the knife mount to engage the knife arm when the blade is in the second position.
 20. The cartridge assembly of claim 19, wherein the stabilizing finger extends over at least one of the spring, the pivot pin, or the knife arm. 